Background: Childbirth dissatisfaction may reduce maternal tendency for subsequent pregnancies and increase maternal request for elective cesarean. This study aimed to investigate predictors of birth satisfaction in a sample of Iranian postpartum women. Methods: This cross-sectional study was conducted on 767 women in early postpartum using a convenience sampling method in 2019. Women’s demographic/obstetrical information were collected. Women completed three questionnaires including the World Health Organization-5 well-being Index (WHO-5 well-being Index), the Birth Satisfaction scale-R (BSS-R), and the Wijma Delivery-Expectancy/experience Questionnaire (W-DEQ) version B. We used univariate general linear model to investigate the relationships between independent variables and birth satisfaction scores. Multiple linear regression analysis was used to determine predictors of birth dissatisfaction. Results: The percentage of women who gave birth by elective cesarean, emergency cesarean, and vaginal birth were 13.2%, 19.06%, and 67.8%, respectively. Predictors of low birth satisfaction were primiparity, low level of well-being, low and moderate satisfaction with pregnancy, moderate satisfaction with spouse’s emotional/financial support, emergency cesarean, severe fear of childbirth, and long duration from admission to delivery. Women who had vaginal birth and were accompanied by a doula reported a higher level of birth satisfaction than those without a doula (p = 0.012). Women who had emergency cesarean accompanied by a doula reported a lower level of birth satisfaction than those without a doula (p = 0.045).Conclusions: Our results indicate that in order to promote birth satisfaction, specific interventions should be designed that enhance maternal well-being, reduce fear of childbirth, and promote spouse’s support. Also, revising and improving admission protocols in maternity hospitals and other measures that help women have a smooth and hassle-free pregnancy can promote birth satisfaction. Further studies should also be conducted in Iran to examine other significant social predictors of birth satisfaction such as interaction between midwives/physicians and patients and respectful attitude of staff members.